As is known in the art, diagnostically relevant particles and rays, such as products of radioactive decay (i.e., beta particles and gamma rays), or x-rays resulting from an x-ray tube, can be detected with a variety of instrumentation the sensitivity of which typically depends on some type of energy width characteristic to the detector material. This characteristic energy width is related to the energy bandgap and, in the case of semiconductors, to the energy levels of dopants in the case of scintillation and other luminescence materials, and to the ionization energies in the case of gas detectors. The energy width also determines the internal amplification factor for detection, which may be defined as the number of signal carriers (e.g., visible photons in the case of scintillators, electrons or holes in the case of semiconductors, and ions in the case of gas detectors) per absorbed energy of the detected entity.
In the case of high energy photons with energies equal or above the energy regime of x-rays, are typically detected using a dual-step conversion of the high energy photons to visible light by means of a scintillation crystal and of the visible light to electrical charge by means of a photodetector. This two-step conversion (wherein each step may have its own internal amplification requirements) typically leads to loss of information and also adds complexity in the detector design. Although a number of existing detector designs use materials that allow for a one-step radiation detection (e.g., Germanium, Cadmium Telluride or Cadmium Zinc Telluride devices which are semiconductors with high enough atomic number and density and low enough bandgap to be sensitive to high energy radiation), their sensitive operation relies upon strong internal and external amplification of the generated charge, in order for the latter to be accurately detected.
It would, therefore, be desirable to provide a one step radiation detection system for detection of a wide range of radiation wavelengths, and for different types of radiation, both charged and neutral, where the need for internal amplification of the generated signal carriers is less of a requirement.